Polyethylene-based arrangement

Abstract

The invention relates to a polyethylene-based arrangement (8) with a thickness of less than 250 µm for the storage of grain, silage, warm or wet industrial products, comprising at least one outer layer (1), at least one inner layer (7), and only one barrier layer (5). The barrier layer (5) is a polyamide layer with a thickness of less than 30 µm. The arrangement (8) includes at least one PE-based functional layer (3) to reduce the oxygen permeability of the polyethylene-based arrangement (8) to less than 50 cm³ / m² d bar according to ASTM D3985.

Description

[0001] The invention relates to a polyethylene-based arrangement with a thickness of less than 250 µm for the storage of grain, silage, warm or wet industrial products, comprising at least one outer layer, at least one inner layer and only one barrier layer, wherein the barrier layer is a polyamide layer with a thickness of less than 30 µm.

[0002] Polyethylene-based materials are used, for example, as silage tubes or tubular silage bags. Tube silage is an efficient, flexible, and environmentally friendly technology for preserving and storing all types of animal feed or wet industrial products in a specially designed tubular liner. Originally developed for ensiling green waste, a wide variety of substrates can now be stored in silage tubes. Silage tubes are also used for composting organic material. Today, for example, beet pulp, as well as corn and grass silage, are also stored in silage tubes.

[0003] A typical silo hose consists of at least two layers, is approximately 120 m long, and has a diameter of 5 m. Accordingly, high demands are placed on a silo hose in terms of tensile strength and puncture resistance.

[0004] Filling silo tubes requires special machines that typically first shred the stored material and then compress it into the tubes. DE 10 2010 046 183 A1 describes such a device.

[0005] Silage bags require a barrier against oxygen and water vapor to maintain the quality of the feed in the silage. Silage is produced through the anaerobic (oxygen-free) fermentation process, in which lactic acid bacteria ferment the plant material. The exclusion of oxygen prevents unwanted microorganisms such as molds or yeasts from decomposing the material and impairing the quality of the silage.

[0006] Oxygen would disrupt the fermentation process and lead to putrefaction, rendering the feed unusable for the animals. If oxygen penetrates the silage tubes, it can cause the oxidation of nutrients, particularly carbohydrates and proteins. This reduces the nutritional value of the silage, negatively impacting animal health and feed efficiency. In an oxygen-rich environment, molds and yeasts can grow, not only spoiling the silage but also producing harmful mycotoxins that can cause illness in the animals. A barrier against water vapor prevents moisture from penetrating the silage from the outside. Too much moisture inside can lead to faulty fermentation, while too little moisture can also disrupt the process.

[0007] Proper moisture control ensures that the silage remains stable and maintains the desired consistency.

[0008] Sealing against oxygen is crucial for silage production. Traditionally, stable polyethylene-based films were used for silage bags. However, the use of these conventional films has repeatedly led to mold growth due to oxygen penetration.

[0009] Conventional films for silo bags based on conventional polyolefins would have to be very thick to ensure sufficient oxygen impermeability and would therefore be heavy and relatively expensive to produce.

[0010] The use of EVOH as a barrier material results in excellent barrier properties, but EVOH cannot provide sufficient mechanical properties for use in silo bags.

[0011] For this reason, films with special barrier arrangements were developed for silo bags. These barrier arrangements consist of polymers that exhibit particularly high impermeability to gases, especially oxygen.

[0012] DE 698 17 012 T2 describes a multi-layered film for agricultural silage products.

[0013] The film has a polyamide layer that acts as an oxygen barrier. The film can consist of two or more layers, e.g., co-extruded layers, of which at least one, or possibly several, layers are made of an insulating plastic. In a multilayer film with at least two insulating layers, these insulating layers can be made of the same plastic material or of different plastic materials, all of which are airtight.

[0014] DE 10 2009 052 948 B4 describes a covering system for silage with a base film made of polyamide and a silage film made of polyethylene.

[0015] Polyamide has excellent puncture resistance, but its tear resistance is often not sufficient for the demanding use of silage hoses in agriculture.

[0016] DE 10 2017 107 060 A1 discloses a method for increasing the tear resistance of a multilayer film. The multilayer film has at least one barrier arrangement having a total thickness to reduce gas permeability. According to the invention, the barrier arrangement is divided into at least two layers to increase the tear resistance.

[0017] As part of its "Green Deal," the European Union aims to reduce the landfilling of plastic waste. By 2030, 55% of plastic packaging waste is to be recycled. This presents entirely new challenges for the production and design of silo bags, hoses, and films.

[0018] To meet the challenges of recycling, packaging design must become increasingly sustainable. This can be achieved, for example, by developing and implementing more mono-material constructions. The challenge lies in achieving the same barrier effect as before with just one recyclable mono-material construction for a silage casing.

[0019] Furthermore, the silo liner must also be able to achieve the same mechanical properties as previously achieved. Otherwise, the silo liners could burst during filling or tear during transport.

[0020] Furthermore, the proportion of known barrier materials such as EVOH and / or polyamide must be reduced to meet recycling requirements, ideally without compromising barrier properties.

[0021] The object of the present invention is to design a polyethylene-based arrangement that is thinner than previously known arrangements in order to meet the future requirements of the Plastics Pact 2025. Furthermore, the arrangement should be fully recyclable. The polyethylene-based arrangement should also be suitable for packaging and storing grain, silage, and warm or moist industrial products. In addition, the polyethylene-based arrangement should exhibit the mechanical properties achieved to date. Finally, the arrangement should be very cost-effective to manufacture in order to be competitive in the price-pressured agricultural sector.

[0022] According to the invention, this objective is achieved by a polyethylene-based arrangement, a method, and a use as described in the dependent main claims. Preferred embodiments are described in the dependent claims, the description, the exemplary embodiment, and the drawings.

[0023] According to the invention, the arrangement comprises at least one functional layer based on PE to reduce the oxygen permeability of the polyethylene-based arrangement to less than 50 cm. 3 / m 2 d · bar according to ASTM D3985.

[0024] The polyethylene-based arrangement can be designed, for example, as a silo bag, silo tube, silo planer or as a silo tarp.

[0025] To fulfill its purpose, a silage liner must have a certain degree of oxygen impermeability. This is the only way to ensure a proper fermentation process during ensiling, for example, within the silage liner itself, or impermeability to chemicals in the case of disinfection films.

[0026] For example, the polyethylene-based arrangement has an oxygen permeability of less than 45 cm. 3 / m 2 d · bar, preferably less than 35 cm 3 / m 2 d · bar, especially less than 25 cm 3 / m 2 d · bar at 23°C and 50% relative humidity according to ASTM D3985.

[0027] The water vapor permeability of dry or moisture-sensitive goods is determined according to DIN 53116 or ASTM D6701-01 using a gravimetric method. A test container filled with a desiccant is sealed with a foil sample and exposed to a defined test climate. The amount of water that penetrates the sample is determined by weighing. The measured water vapor permeability can range from 1 to 200 g / (m³). (2) · d) be detected. The detection limit also depends on the composition and thickness of the sample.

[0028] The polyethylene-based arrangement, for example, has a water vapor permeability of less than 20 g / m². 2 in 24 h according to ASTM D6701-01.

[0029] In one embodiment of the invention, the polyethylene-based arrangement has a water vapor permeability of less than 15 g / m². 2 , preferably less than 10 g / m² 2 , especially less than 5 g / m² 2within 24 hours according to ASTM D6701-01. This makes the storage of grain, silage, warm or wet industrial products particularly advantageous, with the silage being coated for a particularly long time.

[0030] The polyethylene-based arrangement, for example, has a puncture resistance energy of more than 15 mJ according to JAS P1019.

[0031] The puncture resistance is determined according to JAS P1019, whereby a polyethylene-based test specimen is clamped in a specimen holder. The clamping device is designed so that the inner diameter is 10 mm. A probe with a rounded tip punctures the test specimen at a constant speed. The force and elongation required for penetration are determined.

[0032] The polyethylene-based arrangement, for example, has a puncture resistance according to JAS P1019 of more than 25 mJ, preferably more than 30 mJ, and particularly more than 35 mJ. This means the silage film also withstands the demands of filling the silage tube exceptionally well.

[0033] The polyethylene-based arrangement has a tensile strength in MD according to ASTM 1922 of more than 450 kN / m, preferably more than 500 kN / m, and particularly more than 550 kN / m. This makes the silo hose particularly tear-resistant during the filling process as well as during transport and storage.

[0034] The polyethylene-based arrangement has a tensile strength in CD according to ASTM 1922 of more than 300 kN / m, preferably more than 400 kN / m, and particularly more than 500 kN / m.

[0035] The polyethylene-based arrangement has a Spencerian penetration energy according to ASTM 3420 of more than 2000 mJ, preferably more than 2350 mJ, and particularly more than 2700 mJ. Due to its special structure and the specifically selected raw materials, a film for silo bags is produced that can withstand the enormous mechanical stresses that occur during filling or clogging of the bag.

[0036] The Elmendorf test according to DIN 53128 determines the average force in grams or mN required to tear a sample after the tearing process has been initiated. In this test, one or more layers of the film are torn over a specific distance using a pendulum. The force applied during tearing is measured by the loss of potential energy in the pendulum.

[0037] In one embodiment of the invention, the polyethylene-based arrangement exhibits a tensile strength in the machine direction according to Elmendorf DIN 53128 of more than 20 g / µm, preferably more than 25 g / µm, and particularly more than 30 g / µm. This means that the silo liner is optimally prepared for the challenges of filling and effectively prevents slippage of the silo liner.

[0038] The special physical parameters of the silo hose are achieved through the selection and combination of suitable raw materials, with the structure of the silo hose playing a particularly crucial role in achieving these properties.

[0039] At the same time, the special design and construction of a multi-layered silo hose allows the thickness of the hose to be significantly reduced compared to known hoses.

[0040] For example, the polyethylene-based arrangement has a thickness of less than 240 µm, preferably less than 220 µm, and particularly less than 200 µm.

[0041] In a particularly advantageous embodiment of the invention, the thickness of the polyethylene-based arrangements is 180 µm.

[0042] By reducing the thickness of the silo liner while maintaining its excellent mechanical properties, the requirements of the EU Plastics Pact can be met. The volume of polyethylene-based systems is significantly reduced, even though the same quantity of silo liners can be used.

[0043] The polyethylene-based arrangement, for example, has a seven-layer structure.

[0044] In another variant, the polyethylene-based arrangement has a five-layer structure, whereby, in contrast to the seven-layer variant, the outer and inner layers are not each designed as a double layer.

[0045] A version with nine layers is also conceivable.

[0046] The polyethylene-based arrangement, for example, has a seven-layer structure. In the middle, at least one central layer is surrounded by a barrier layer and a functional layer.

[0047] In one variant of the invention, a connecting layer is also arranged between the barrier layer and the outer layer, and a connecting layer is also arranged between the functional layer and the inner layer.

[0048] In another embodiment, the barrier layer and the functional layer can also be arranged in reverse order.

[0049] For example, the polyethylene (PE) of at least one functional layer based on PE has a density according to ISO 1183-1 of more than 0.925 g / cm³. 3 and less than 0.930 g / cm³ 3 .

[0050] The molecular weight distribution (MWD) describes the distribution of molecular weights or chain lengths of molecules in a sample, particularly in polymers. Since polymers consist of chains of varying lengths, they do not have a uniform molecular mass, but rather a range of masses. The molecular weight distribution indicates how these masses are distributed within the sample. A measure of the width of the molecular weight distribution is defined as the polydispersity index (PDI).

[0051] A PDI value of 1 means that all molecules have the same mass (monodisperse), while higher values ​​indicate a broad distribution (polydisperse). The molecular weight distribution influences the properties of polymers, such as viscosity, melting point, mechanical strength, and solubility. Polymers with a narrow distribution (low PDI) often exhibit more uniform behavior, while polymers with a broad distribution (high PDI) can have more complex properties. Methods such as gel permeation chromatography (GPC) or light scattering are used to measure the molecular weight distribution in polymers.

[0052] In one variant of the invention, the PE of the at least one functional layer on a PE basis has a PDI according to ISO 16014 of less than 2.

[0053] Short-chain branching (SCB) refers to the presence of short side chains in the main chain of a polymer, typically in polyolefins such as polyethylene or polypropylene. These side chains often consist of only a few carbon atoms (e.g., methyl, ethyl, or butyl groups) and are formed by incomplete polymerization processes, such as those that occur in the production of low-density polyethylene (LDPE) or certain copolymers.

[0054] Short branching (SCB) reduces the density of the polymer because the branching prevents the molecular chains from aligning tightly. The short branches decrease the polymer's ability to form ordered, crystalline structures, potentially resulting in a semi-crystalline or amorphous material. The presence of SCB affects the polymer's flexibility, strength, and toughness. Polymers with higher SCB content typically have a lower melting point.

[0055] The PE of at least one functional layer on a PE basis has, for example, a short chain branching (SCB) of 5 - 20 SCB per 1000 carbon atoms.

[0056] Elongation at break is a mechanical parameter that describes a material's ability to stretch before fracturing under stress. It is expressed as the percentage change in length relative to the material's original length. Materials with high elongation at break can stretch considerably without fracturing, indicating high ductility or elasticity.

[0057] In one variant of the invention, the PE of the at least one functional layer based on PE has an elongation at break according to ISO 527-1 of more than 400%, preferably more than 550%, and in particular more than 700%.

[0058] All these special properties of the PE of the PE-based functional layer create a functional layer that comes very close to the mechanical properties and barrier properties of a polyamide, whereby a conventional barrier layer can be replaced by this special PE-based functional layer.

[0059] This provides silo hoses that, while exhibiting high oxygen impermeability and flexible behavior, also have high tear resistance, thus preventing unwanted bursting or tearing, and at the same time only a relatively small thickness of the multilayer film is required, making the polyethylene-based arrangement according to the invention relatively lightweight.

[0060] Furthermore, the embodiment of the arrangement according to the invention based on polyethylene represents the first realization of a variant that is also considered recyclable according to the new requirements of the European Union and has also proven itself in the practical implementation of recycling through the reduced use of polyamide with only a very thin layer.

[0061] The thickness of the barrier layer is, for example, more than 5 µm and less than 20 µm. This means that the barrier layer is particularly thin, saving material, yet still has excellent barrier properties.

[0062] Furthermore, the proportion of the barrier layer is less than 5 wt.% of the polyethylene structure and thus fully complies with the requirements of the European Union for the recyclability of plastic films.

[0063] For example, the polyamide of the barrier layer has a density according to ISO 1183-1 of more than 1.08 g / cm³. 3, preferably more than 1.10 g / cm³ 3 and / or less than 1.20 g / cm³ 3 , preferably less than 1.16 g / cm³ 3 .

[0064] In one variant of the invention, the polyamide of the barrier layer has a breaking strength of more than 80 MPa, preferably more than 100 MPa and / or less than 200 MPa, preferably less than 160 MPa.

[0065] DIN EN ISO 11357 is a standard for determining the thermal properties of plastics, including melting and softening temperatures, specific heat capacity, thermal conductivity, and other heat transfer properties. The standard specifies various methods for thermal analysis, including differential scanning calorimetry (DSC), thermogravimetry (TG), dynamic mechanical analysis (DMA), and other techniques. These methods allow for the characterization of the temperature dependence of various thermal properties.

[0066] The polyamides used for silage films typically have melting points above 220 °C. Special polyamides, for example, have melting points of 207 °C. However, these temperatures are still too high to recycle the silage films, which preferably consist of a high polyethylene content, according to their intended use. The high melting point of the polyamide results in low bubble stability and high tooling temperatures, which negatively affect the mechanical properties of the resulting products.

[0067] In a particularly advantageous embodiment of the invention, the polyamide of the barrier layer has a melting point of less than 179 °C according to DIN EN ISO 11357. This previously unattainable low melting point of a polyamide component results in a polyethylene-based arrangement, especially for silo hoses, which can be recycled to an excellent standard.

[0068] In particular, the low melting point of the polyamide in the barrier layers leads to a recycled polyethylene-based arrangement which, due to the lower overall melting point, is better suited for all processes that allow the recycled material to be reused in a valuable way.

[0069] In one variant of the invention, at least one connecting layer borders the barrier layer and the functional layer.

[0070] For example, a middle layer is arranged between the barrier layer and the functional layer.

[0071] The middle layer, for example, consists of a very soft polyethylene (PE).

[0072] This very soft polyethylene can be made from LDPE, mLLDPE, or a mixture. Polyethylene (PE) has a density greater than 0.906 g / cm³. 3 and less than 0.912 g / cm³ 3 , preferably less than 0.910 g / cm³ 3 .

[0073] At least one bonding layer and the central layer contain a proportion of maleic anhydride-grafted concentrate of more than 5 wt% and less than 20 wt%.

[0074] The concentrate grafted with maleic anhydride, for example, has a density according to ISO 1183-1 of more than 0.919 g / cm³. 3 and less than 0.921 g / cm³ 3 , and an MFI (at 190 °C and 2.16 kg) according to ISO 1133-1 is greater than 0.1 g / 10 min and less than 0.5 g / 10 min.

[0075] The bonding layer consists, for example, of at least 60 wt% LLDPE with an MFI of more than 0.8 and at least 5 wt% maleic anhydride-grafted concentrate. This simultaneously ensures enormous tear strength and secures the bond to the barrier layer and the functional layer.

[0076] In one variant of the invention, the proportion of LLDPE in the compound layer is more than 70 wt.% and less than 90 wt.%.

[0077] The production of LLDPE is initiated using transition metal catalysts, particularly Ziegler or Philips-type catalysts. The actual polymerization process can be carried out either in solution or in gas-phase reactors. Typically, octene is the comonomer in solution, while butene and hexene are copolymerized with ethylene in a gas-phase reactor. LLDPE has higher tensile strength and higher impact and puncture resistance than LDPE. It is very flexible and elongates under stress. It can be used to produce thinner films that exhibit better resistance to stress cracking. It has good chemical resistance and good electrical properties. However, it is not as easy to process as LDPE, has a lower gloss, and is less susceptible to heat sealing.

[0078] For example, the proportion of a concentrate grafted with maleic anhydride in the compound layer is more than 10 wt.% and less than 20 wt.%.

[0079] The flow behavior of polyolefins is described by the melt flow rate (MFI) according to ISO 1133-1, typically at a temperature of 190 °C for polyethylene under a load of 2.16 kg, 5 kg, or 21.6 kg. A higher melt flow index correlates with a lower average molecular weight of the polymer. The higher the melt flow index of a polymer, the lower its melt viscosity, which is advantageous for high throughput of the extrusion system. Conversely, polymers with a high molecular weight, i.e., a low melt flow index, are advantageous with regard to mechanical stability, particularly tensile strength or toughness.

[0080] For example, the compound layer contains a proportion of LLDPE with a density according to ISO 1183-1 of more than 0.918 g / cm³. 3 and less than 0.922 g / cm³ 3 and whose MFI (at 190 °C and 2.16 kg) according to ISO 1133-1 is more than 0.9 g / 10 min and less than 1.1 g / 10 min.

[0081] The compound layer contains, for example, a proportion of a maleic anhydride-grafted concentrate whose density according to ISO 1183-1 is more than 0.919 g / cm³ 3 and less than 0.921 g / cm³ 3 and whose MFR (at 190 °C and 2.16 kg) according to ISO 1133-1 is more than 0.1 g / 10 min and less than 0.5 g / 10 min.

[0082] In one embodiment of the invention, the outer layer and the inner layer comprise at least 50 wt.% of mLLDPE with an MFI of less than 0.6 and at least 15 wt.% of LLDPE with an MFI of more than 0.8.

[0083] For example, the proportion of mLLDPE in the outer layer and / or the inner layer is more than 55% by weight and less than 80% by weight. The proportion of mLLDPE in the outer layer and / or the inner layer advantageously increases the stability of the silage bag.

[0084] The outer layer and / or the inner layer contains a proportion of LLDPE. The LLDPE content significantly increases the tensile strength of the outer layer and / or the inner layer. For example, the LLDPE content in the outer layer and / or the inner layer is more than 15% by weight and / or less than 35% by weight.

[0085] In one embodiment of the invention, the outer and / or inner layer comprises a proportion of mLLDPE whose density according to ISO 1183-1 is greater than 0.920 g / cm³. 3 is and less than 0.922 g / cm² 3 and whose MFR (at 190 °C and 2.16 kg) according to ISO 1133-1 is more than 0.3 g / 10 min and less than 0.55 g / 10 min.

[0086] For example, the outer and / or inner layer contains a proportion of LLDPE whose density according to ISO 1183-1 is more than 0.918 g / cm³. 3 and less than 0.922 g / cm³ 3 , and whose MI (at 190 °C and 2.16 kg) according to ISO 1133-1 is more than 0.85 g / 10 min and less than 1.5 g / 10 min.

[0087] In one variant of the invention, the outer layer contains a proportion of titanium dioxide. TiO2 Preferably, this is coated TiO2. The titanium dioxide content makes the outer layer white, resulting in excellent reflection of sunlight and thus excellent protection of the silage material.

[0088] The titanium dioxide is, for example, integrated into a white polybatch. In one embodiment of the invention, the outer layer has a white polybatch content of more than 5 wt.% and less than 20 wt.%.

[0089] In another embodiment of the invention, the compound layers also contain a proportion of white polybatch with titanium dioxide, wherein the proportion in the intermediate layer is more than 5 wt.% and less than 20 wt.%.

[0090] For example, the functional layer also contains a proportion of white polybatch with titanium dioxide, with the proportion in the intermediate layer being more than 5 wt.% and less than 20 wt.%.

[0091] The CIELAB color space is typically used to evaluate and control the color properties of polymer films in various industries. This color space provides a standardized, device-independent framework for measuring color and reflectance, making it ideal for ensuring consistency and accuracy in polymer film production.

[0092] During the production process, manufacturers can use spectrophotometers to measure the L*, a*, and b* values ​​of the films. These devices record how the film reflects or transmits light and then convert this data into Lab values. This information allows manufacturers to assess whether the color of a film meets the specified target values ​​or tolerances.

[0093] For example, the outer layer or the polyethylene-based arrangement has a reflectance value according to Lab of more than 70%, preferably more than 75%, and particularly more than 80%. In this advantageous way, the high-energy solar radiation can be reflected, thus effectively protecting the contents of the silo tube.

[0094] In one variant of the invention, the inner layer contains a proportion of a black pigment.

[0095] For example, the inner layer also contains a proportion of black polybatch, with the proportion in the inner layer being more than 5 wt.% and less than 20 wt.%.

[0096] According to the invention, a polyethylene-based assembly is produced by a process in which an outer layer of polyethylene, a barrier layer of polyamide, three bonding layers and an inner layer of polyethylene are produced by coextrusion, wherein at least one functional PE-based layer is coextruded with a special PE to the polyethylene-based arrangement in order to reduce the thickness to less than 250 µm and the oxygen permeability to less than 30 cm 3 / m 2 d · bar according to ASTM D3985.

[0097] The extruders for blown film coextrusion are typically arranged in a ring around the blowing ring. The raw material, usually plastic granules or powder, is fed into the hopper. The hopper ensures that the material is fed evenly into the extruder. The extruder screw is the central element of the extruder and is driven by an electric motor inside the extrusion cylinder. The screw is helical and rotates to melt the material and advance the plastic. The screw is divided into different zones, with the temperature increasing zone by zone from the hopper to the die. For this purpose, the extrusion cylinder is designed as a heated vessel with multiple heated zones to ensure precise temperature control along the extruder screw. The die is located at the end of the extrusion cylinder. There, the molten plastic strand is formed before being fed to the blowing ring.In the blowing ring, the molten plastic strand is blown into a flat tube, which is then inflated into a bubble. The blowing ring is temperature-controlled to regulate the temperature of the molten film. After the bubble has formed, the film passes through a cooling section where cooling air currents or water sprays are used to lower the temperature and stabilize the film. The drawing device pulls the extruded film away from the bubble, ensuring a uniform thickness and width.

[0098] This process determines the final mechanical properties of the polyethylene fibers. The finished polyethylene-based assembly is then wound onto a winder.

[0099] The special temperature guidance and control results in a polyethylene-based arrangement which, due to its properties, especially its melting temperature and its almost pure composition, is advantageously recyclable.

[0100] According to the invention, the polyethylene-based arrangement is used as a reusable silo tube for storing grain, silage, warm or moist industrial products.

[0101] This creates a polyethylene-based arrangement that, while exhibiting high oxygen impermeability and flexibility, also possesses high tensile strength, thus preventing unwanted bursting or tearing. At the same time, only a relatively small thickness of the polyethylene-based arrangement is required, making the silo liner according to the invention relatively lightweight. The use of the PE-based functional layer allows for a particularly cost-effective production of the arrangement.

[0102] Further advantages and features of the invention will become apparent from the description of an exemplary embodiment with reference to the drawings and from the drawings themselves.

[0103] In this context Fig. a schematic representation of the polyethylene-based arrangement, Fig. a further schematic representation of the polyethylene-based arrangement.

[0104] Fig. show a polyethylene-based arrangement 8 with seven layers for a silo hose.

[0105] In this embodiment, the outer layer 1 consists of a proportion of mLLDPE, wherein the outer layer 1 comprises 61 wt% of mLLDPE with a melting point of 113 °C and wherein the MFI of the mLLDPE is 0.45. Furthermore, the outer layer 1 contains a proportion of LLDPE, wherein the outer layer 1 comprises 25 wt% of LLDPE with a melting point of 119 °C and wherein the MFI of the LLDPE is 1.0. The outer layer 1 also contains a proportion of white masterbatch, wherein the outer layer 1 comprises 7 wt% of white masterbatch and the MFI of the white masterbatch is 15.0. In addition, the outer layer 1 contains additives and flow aids in the amount of 6 wt%.

[0106] Layers 2 and 6 consist of a proportion of LDPE, wherein layers 2 and 6 comprise 53.5 wt% of an LDPE with a melting point of 116 °C and a melting factor index (MFI) of 0.27. Layers 2 and 6 also contain a proportion of another LDPE, wherein layers 2 and 6 comprise 20 wt% of an LDPE, with an MFI of 0.25. Layers 2 and 6 also contain a proportion of white masterbatch, wherein layers 2 and 6 contain 12 wt% of a white masterbatch, with an MFI of 15.0. The proportion of a maleic anhydride-grafted concentrate in layers 2 and 6 is 10 wt%, with an MFI of 0.3. Furthermore, the bonding layers 2 and 6 contain additives and flow aids amounting to 4 wt.%.

[0107] The middle layer 4 consists of a very soft LDPE, with the LDPE having a density of 0.910 g / cm³. 3 exhibits the following characteristics. The proportion of a concentrate grafted with maleic anhydride in the middle layer is 10 wt.%.

[0108] The barrier layer 5 consists of a copolyamide PA 6 / 6.6, where the melting point of the copolyamide PA 6 / 6.6 is 179 °C.

[0109] Functional layer 3 consists of a PE component with a melting point of 124 °C, where the MFI of the PE is 0.85 according to ASTM D1238. The PE has a dart drop impact of 2100 g according to ASTM D1709 and a turbidity of 61% according to ASTM D1003.

[0110] Fig. 1 and Fig. Figure 2 shows different arrangements of the barrier layer 5 and the functional layer 3. In one embodiment, the functional layer 3 is arranged close to the outer layer 1, and in another embodiment, the barrier layer 5 is arranged close to the outer layer 1.

[0111] The inner layer 7 consists of a proportion of mLLDPE, wherein the inner layer 7 comprises 63.5 wt% of mLLDPE with a melting point of 113 °C and where the MFI of the mLLDPE is 0.45. Furthermore, the inner layer 7 contains a proportion of LLDPE, wherein the inner layer 7 comprises 25 wt% of LLDPE with a melting point of 119 °C and where the MFI of the LLDPE is 1.0. The inner layer 7 also contains a proportion of black masterbatch, wherein the inner layer 7 contains 8 wt% of black masterbatch and where the MFI of the black masterbatch is 15.0. Additionally, the inner layer 7 contains additives and flow agents in the amount of 4 wt%. QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] DE 10 2010 046 183 A1

[0004] DE 698 17 012 T2

[0012] DE 10 2009 052 948 B4

[0014] DE 10 2017 107 060 A1

[0016]

Claims

[1] A polyethylene-based arrangement (8) with a thickness of less than 250 µm for the storage of grain, silage, warm or wet industrial products, comprising: - at least one outer layer (1) - at least one inner layer (7) - only one barrier layer (5), wherein the barrier layer (5) is a polyamide layer with a thickness of less than 30 µm, characterized by , that the arrangement (8) comprises at least one PE-based functional layer (3) to reduce the oxygen permeability of the polyethylene-based arrangement (8) to less than 50 cm 3 / m 2 d bar according to ASTM D3985. [2] Polyethylene-based arrangement according to claim 1, characterized by , that the polyethylene-based arrangement (8) has a water vapor permeability of less than 20 g / m² 2 within 24 hours according to ASTM D6701-01. [3] Polyethylene-based arrangement according to claim 1 or 2, characterized by, that the polyethylene-based arrangement (8) exhibits a puncture energy according to JAS P1019 of more than 15 mJ. [4] Polyethylene-based arrangement according to at least one of the preceding claims, characterized by , that the polyethylene-based arrangement (8) has a tensile strength in MD according to ASTM 1922 of more than 400 kN / m. [5] Polyethylene-based arrangement according to at least one of the preceding claims, characterized by , that the PE of the at least one functional layer (3) on a PE basis has a density of more than 0.925 g / cm³ 3 and less than 0.930 g / cm³ 3 exhibits. [6] Polyethylene-based arrangement according to at least one of the preceding claims, characterized by , that the PE of the at least one functional layer (3) on a PE basis has a molecular weight distribution (PDI) according to ISO 16014 of less than 2. [7] Polyethylene-based arrangement according to at least one of the preceding claims, characterized by, that the PE of at least one functional layer (3) on a PE basis has a short chain branching (SCB) of 5 - 20 SCB per 1000 carbon atoms. [8] Polyethylene-based arrangement according to at least one of the preceding claims, characterized by , that the PE of the at least one functional layer (3) on a PE basis has an elongation at break according to ISO 527-1 of more than 400%, preferably more than 550%, in particular more than 700%. [9] Polyethylene-based arrangement according to at least one of the preceding claims, characterized by , that at least one connecting layer (2, 6) is adjacent between the barrier layer (5) and the functional layer (3). [10] Polyethylene-based arrangement according to at least one of the preceding claims, characterized by, that the polyethylene-based arrangement (8) comprises a central layer (4) made of a very soft polyethylene (PE) wherein the polyethylene (PE) has a density of less than 0.912 g / cm³ 3 exhibits. [11] Polyethylene-based arrangement according to at least one of the preceding claims, characterized by , that at least one compound layer (2, 6) and the central layer (4) has a proportion of a maleic anhydride-grafted concentrate of more than 5 wt.% and less than 20 wt.%. [12] Polyethylene-based arrangement according to at least one of the preceding claims, characterized by , that the outer layer (1) has a reflection according to the laboratory value of more than 70%. [13] Polyethylene-based arrangement according to at least one of the preceding claims, characterized by, that the polyethylene-based arrangement (8) has a thickness of less than 240 µm, preferably less than 220 µm, in particular less than 200 µm. [14] Method for producing a polyethylene-based arrangement (8) comprising the following steps: - Extrusion of an outer layer (1) of a polyethylene, - Extrusion of only one barrier layer (5), wherein the barrier layer (5) is a polyamide layer with a thickness of less than 30 µm, - Extrusion of an inner layer (7) from a polyethylene, characterized by , that at least one PE-based functional layer (3) is co-extruded onto the polyethylene-based arrangement (8) to reduce the thickness to less than 250 µm and to reduce the oxygen permeability to less than 30 cm 3 / m 2 d bar according to ASTM D3985. [15] Use of a polyethylene-based arrangement (8) according to any one of claims 1 to 13 as a reusable silo liner for storing grain, silage, warm or moist industrial products.

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